Retractable cord device



s. LADANY RETRACTABLE CORD DEVICE March 12; 1968 Filed March 23, 1965INVENTOR SHAUL LRDHNY ATTORNEY United States Patent 3,372,887RETRACTABLE CORE) DEVICE Shani Ladany, 431 Riverside Drive,

New York, N .Y. 10025 Filed Mar. 23, F966, Ser. No. 536,695 4 Claims.(Cl. 242--'7.13)

ABSTRACT OF THE DISCLOSURE A retractable cord device comprises ahousing, a springloaded drum rotatably mounted within the housing, acord adapted to be wound upon the drum, the drum being formed with aspiral groove for the reception of the cord. The housing is formed witha shaped orifice through which the cord passes as it is unwound from thedrum, the orifice including an inwardly extending annular lip whichsnugly engages the cord and applies a resistance to the passage of thecord. In a modification, the mid-point of the cord is fixed to the drumand the two ends of the cord pass through a pair of adjacently-disposedorifices. A cord guide is provided between the orifices and the drum fordisplacing the cord ends from the perpendicular as they pass through theorifices.

The present invention relates to retractable cord devices and isparticularly, but not exclusively, useful with respect to electricalcords.

An object of the invention is to provide a winding drum type ofretractable cord device which is simple in construction and efiicient inoperation. A further object is to provide such a device particularlyuseful for electrical cords in that it does not require a slidingcontact arrangement for maintaining electrical continuity through thecord while the winding drum is rotated.

The various novel features of my invention are set forth withparticularity in the appended claims, but will be better understood byreference to the accompanying drawings, in which FIGS. 1 and 2 arelongitudinal sectional views of two forms of retractable cord devicesconstructed in accordance with the invention.

The device of FIG. 1 includes a cylindrical housing 2 which ispreferably made of two parts held together by fasteners 4-. Disposedwithin the housing is a drum 6 formed with a spiral groove 8 on itsperipheral surface for the reception of the electrical cord 10 adaptedto be wound upon, and unwound from, the drum during the retraction andextension of the cord. The drum 6 is formed with a pair of vertical enddisks or plates 12 and 14, plate 12 being journalled within a recess inhousing 2, and plate 14 being journalled on a pin 16 formed with asquare head 18 received in a square-opening in the housing 2 to preventthe rotation of the pin. A coil spring 20 is disposed within a recessformed at the end of drum 6 adjacent to plate 14. One end of the springis fixed to pin 16 by being inserted within slot 17 thereof, and theother end is fixed to the drum, the spring thus storing energy uponrotation of the drum in the unwinding direction and releasing the energyto drive the drum in the winding direction. For locking the drum againstrotation when the cord is extended, there may be provided a toothedwheel 22 fixed to pin 16 and a pair of pawls 24 and 26 pivotably mountedon pins 24 and 26 carried by end plate 14. Such locking means are wellknown and are effective to lock the drum against rotation and to releasethe drum when a quick snap is given to the cord, permitting it to beretracted by spring 20.

Housing 2 is formed with a shaped orifice 30 through which one end ofthe cord 10 (i.e. the end containing the socket 32) passes as it isunwound from the drum. Orifice 30 has a diameter substantially equal tothat of cord 10 and is shaped with an inwardly extending annular lip 30which snugly engages the cord and applies a resistance to the cord as itpasses through the orifice. That is, as the cord is pulled through theorifice by the springloaded drum while being rewound onto the drum, itmakes continuous frictional contact wtih the lip of the orifice, exceptfor the very short time it is substantially perpendicular to the orificeas it passes therethrough from the drum. The resistance produced by thisfrictional Contact is suflicient so that the cord is placed undertension as it is retracted within the housing, and therefore will morepositively seat itself within groove 8 on the drum as it is retracted.When the cord has completed one layer of windings on the drum, thewindings themselves form a spiral groove upon which the second layer ofwindings will form, and so on until the complete cord is wound upon thedrum.

The opposite end of the cord 10 is fixed to the housing by fastener 34and terminates in an electrical plug 36.

Drum 6 is formed with a cylindrical cavity 40 in which is disposed aspan 10 of the cord between its plug 36 (Le. the fixed end) and thefirst winding on drum 6. The end of span 10' opposite to the plug endpasses through a bore 42 in the drum to its peripheral surface and isfixed by a fastener 43. Span 10 is given a preformed spiral in thedirection opposite to the unwinding direction of the drum. In thismanner, even though one end of the cord is fixed the drum may be rotatedfor extending or retracting the opposite end of the cord without theneed of a sliding contact arrangement between the cord ends. By givingthe span a spiral in the direction opposite to the unwinding directionof the drum, the drum may be rotated a large number of rotations beforethe span of the cord becomes taut.

FIG. 2 illustrates another device constructed in accordance with theinvention. In this device, the need of sliding contacts is avoided byhaving both ends of the cord wound and unwound from the drum 106. Forthis purpose, housing 102 includes a pair of shaped orifices and 131,both similar to orifice 30, through which orifices the socket end 132and the plug end 136 of the cord pass as the two ends are simultaneouslyWithdrawn from the device. The peripheral surface of drum 106 is formedwith a pair of spiral grooves 108 and 109 which receive the two ends ofthe cord as they are wound upon the drum. The mid-point of the cord isfixed to the drum by a fastener 111. The remaining structure of thedrum, particularly its end plates, spring, and locking elements, may allbe the same as in the FIG. 1 embodiment.

In FIG. 2, there is also provided a cord guide disposed between theshaped orifices and the drum. The cord guide displaces from theperpendicular the exit angle of the cord as it passes through itsorifice, thereby increasing the resistance and tension of the cordduring its retraction. Actually, in FIG. 2 there are two such cordguides, one for each of the two ends of the cord wound and unwound fromthe drum. The cord guides in the FIG. 2 embodiment are constituted by apair of openings and 152 in a plate or partition 154- formed by thehousing between the drum 106 and the shaped orifices 130 and 131. Theopenings 150 and 152 are disposed so that they displace their respectiveends of the cord from the perpendicular as these ends pass throughorifices 130 and 131. The resistance on the ends of the cord is therebyincreased, and therefore the cord will more positively seat within thegrooves 108 and 109 as the cord is retracted by the drum spring.

A similar type of cord guide could of course also be provided in theFIG. 1 design.

It is thus seen that in both embodiments, an even tension is applied tothe cord as it rewinds itself upon the drum thus assuring that it willrewind properly. Also,

there is no necessity for the provision of sliding contacts, such asslip rings or the like, since in FIG. 1 the span 10 within the cavity indrum 6 permits the rotation of the drum even though one end of the cordis fixed, and in FIG. 2, both ends of the cord are unwound and wound atthe same time.

Many changes, variations and applications of the illustrated embodimentsmay be made within the scope of the invention as defined in thefollowing claims.

I claim:

1. A retractable cord device comprising a housing, a drum rotatablymounted within said housing, a cord adapted to be wound upon and unwoundfrom said drum for retracting and extending the cord, said drum beingformed with a spiral groove for the reception of said cord when woundthereupon and spring means adapted to store energy upon rotation of thedrum in the unwinding direction and to release energy to drive the drumin the winding direction, said housing being formed with an orificethrough which one end of the cord passes as it is unwound from the drum,said orifice having a diameter substantially equal to that of the cordand being shaped with an inwardly extending annular lip which snuglyengages the cord and applies a resistance to the passage of the cordtherethrough so that the cord is placed under tension as it is retractedwithin the housing and wound onto the spiral groove of said drum.

2. A device as defined in claim 1, wherein said housing includes a pairof said shaped orifices formed adjacent to each other, the cord beingfixed at its mid-point to said drum, and both ends of the cord beingwound upon and unwound from said drum at the same time and passinglthrough said pair of shaped orifices as said cord is retracted andextended.

3. A device as defined in claim 2, wherein said housing includes a cordguide disposed between said shaped orifices and drum, said cord guidedisplacing from the perpendicular the exit angle of both ends of thecord as they pass through the orifices thereby increasing the saidresistance and tension of the cord.

4. A device as defined in claim 1, wherein the opposite end of said cordis fixed to said housing and wherein said drum is formed with aninternal cavity and with a bore communicating same with the peripheralsurface of the drum, a spiralled span of the cord at said opposite endbeing disposed within said cavity and extending through said bore to theperipheral surface of said drum, permitting the drum to be rotated forextending or retracting said one end of the cord while said opposite endis fixed to said housing.

References Cited UNITED STATES PATENTS 416,255 12/1889 Cortlell242-107.1l 1,455,715 5/1923 Danese 242-107.l2 2,572,856 10/1951 Hallberg242107 3,061,234 10/1962 Morey 242-107.1 3,144,218 8/1964 Tepe 242-10713,260,472 7/1966 Zolot 242107.12

FOREIGN PATENTS 42,863 8/1930 Denmark. 822,381 11/1951 Germany.

WILLIAM S. BURDEN, Primary Examiner.

